Devices for firing objects of the class of projectiles, plugs, pins and nails



Feb. 7, 1967 c. ROSSELET 3,

DEVICES FOR FIRING OBJECTS OF THE CLASS OF PROJECTILES, PLUGS, PINS ANDNAILS 2 Sheets-Sheet 1 Filed April 16, 1965 Feb. 7, 1967' c. ROSSELET 3,

DEVICES FOR FIRING OBJECTS OF THE CLASS OF PROJECTILES, PLUGS, PINS ANDNAILS Filed April 16, 1965 2 Sheets-Sheet 2 United States Patent3,302,319 DEVICES FOR FIRING OBJECTS OF THE CLASS OF PROJECTILES, PLUGS,PINS AND NAILS Claude Rosselet, Founex, near Nyon, Switzerland, as-

signor to Corat S.A., Compagnie de Recherches et dApplicationsTechniques, Lenzerheide, Grisons, Switzerland, a Swiss company FiledApr. 16, 1965, Ser. No. 448,624 Claims priority, application France,Apr. 22, 1964, 971,871, Patent 1,422,054 2 Claims. (Cl. 421) The presentinvention has for its object a device for firing objects of the class ofprojectiles, plugs, pins, nails, etc., which are intended to bepropelled under the action of an explosive charge of the type in whichthe ignition of the charge takes place spontaneously under the action ofan increase in pressure, that is to say which does not require anypriming product but which takes placeunder the action which is known bythe name of diesel effect.

The device in accordance with the invention, which can be a fire-arm,sealing-gun, etc., is characerized in that the loading chamber which islocated behind a barrel and which is intended to receive the explosivecharge together with the object to be fired communicates with acompressed-air pump having a piston so designed as to be capable ofbeing brought manually into the cocked position in opposition to thethrust exerted by elastic means and to carry out a suction stroke, thecommencement of the working stroke or delivery stroke of said pistonwhich is produced by said elastic means being controlled by releasingmeans in such a manner as to compress the air within the pumpcylinder-and to discharge said compressed air into the loading chamberwith a view to igniting the explosive charge.

In one preferred form of embodiment of the novel firing device, saiddevice is further characterized by the following points and combinationsthereof:

The compressed-air pump is coaxial with the gun barrel and movablerelatively to said barrel so as to provide access to the loadingchamber;

The piston is integral with a skirt and with an axial rod which delimitswith said skirt an annular space in which the elastic means aredisposed, the said elastic means advantageously consisting of a coilspring which surrounds said axial rod;

The piston is provided on the front face thereof with an axial recess ofsubstantially frusto-conical shape to which there corresponds a boss ofcomplementary shape which is provided at the end of the pump cylinderand in which are formed ducting means for permitting said cylinder tocommunicate with the loading chamber;

The ducting means comprise at least one duct which has its outlet in thefrusto-conical surface of the cylinderend boss;

The aforesaid duct encloses a valve which is normally open but which isdesigned to seal off said duct under the action of the high pressure ofthe combustion gases produced by the ignited explosive charge;

The pump cylinder which is adapted to slide with respect to the gunbarrel is lockable in the position in which said cylinder-end is incontact with the rear end of said gun barrel;

The cocking stroke of the piston is controlled by means of ahand-operated toggle lever which is articulated at a fixed point of thedevice and is engaged with the skirt of the piston;

That portion of the toggle lever which is engaged with the skirt of thepiston is adapted to slide within a longitudinal groove of said skirt;

That portion of the toggle lever which is operable by hand comprisesreleasable locking means for maintaining said lever in the restposition.

353M319 Patented Feb. 7, 1967 The invention also has for its object anammunition unit which is designed for use in the device hereinabovereferred-to, said ammunition unit being characterized in that the objectto be fired which forms part of said unit (namely a projectile, plug,pin, nail and the like) is adapted to form, prior to the propulsionthereof, a valving means for sealing off the rear end of the gun barreland that said object is integral at the rear end thereof with areceptacle which contains the explosive charge, said receptacle havingpreferably the shape of a skirt which is open at the rear end.

In the preferred forms of embodiment thereof, the novel ammunition unitis further characterized in that the charge which is placed within theskirt is so shaped as to have a large free surface and thus to provide alarge area of contact with the compressed air which is intended toinitiate the ignition of said charge. The large free surface referred-tois preferably obtained by means of longitudinal splines formed at theperiphery of the charge.

Further particular features and characteristics of the invention will bebrought out by the following description of one embodiment in the formof a rifle to which this invention applies, said embodiment being givensolely by way of example and not in any limiting sense in view of thefact that this novel device can also be designed in other forms such asa sealing gun or pistol (or any other propulsion devices of likenature), the following description I being made in reference to theaccompanying drawings, wherein:

FIG. 1 is a partial longitudinal sectional view of a portion of therifle in which neither the trigger nor the firing mechanism have beenshown for the sake of clarity;

FIG. 2 is a view in elevation of that portion of the rifle which isshown in partial cross-section in FIG. 1;

FIG. 3 is a sectional view on a larger scale showing that portion of therifle which includes the rear portion of the barrel and the frontportion of the compressed-air P p;

FIG. 4 is a sectional view taken along the line IVIV of FIG. 3;

FIG. 5 is a longitudinal sectional view of an ammunition unit which isintended to be employed with the rifie;

FIG. 6 is a transverse sectional view taken along the line VI-VI of FIG.5;

FIG. 7 is a view in elevation of an alternative form of ammunition unit;

FIG. 8 is a view which is similar to the preceding, show ing anotheralternative form of the ammunition unit.

In accordance with the invention, the rifle which is designed for thepractical application of the invention consists of a receiver 1, thefront end of which is made integral by any suitable means with anannular support 2 in which is fixed the rear portion of the gun barrel3. The assembly 1, 2, 3 is mounted in the usual manner on the stock B.

Beneath the gun barrel is pivotally mounted on the pin 4 carried by thestock an operating arm 5 to which is pivotally coupled at 7 there-cocking linked-rod 6 which forms a toggle-lever with the arm 5.

A pump cylinder 3 is adapted to slide freely within the receiver 1 andthe front end of said pump cylinder is formed by a cylinder head 9 inthe front face of which is formed a f-rusto-conical recess which isadapted to cover and close off in gas-tight manner the rear end ofcomplementary frustoconical shape of the gun barrel 3, the rear end ofthe bore of which opens into the loading chamber 3a.

The assembly which is formed by the cylinder 8 and the head 9 which isintegral therewith forms a movable breech bolt which is slidable withinthe receiver 1 and which is integral with the operating handle 0. Saidoperating handle controls the opening (shown in chaindotted lines) andclosing of the breech bolt and serves to secure the breech bolt in thelocked position when said lever is locked against the shoulder a of thereceiver.

Within the pump cylinder 8 is located a moving system 19 which isadapted to slide therein and which is associated with the cocking andfiring mechanism which can be of any suitable type and which has notbeen shown in the drawings. The moving system 19 consists of a piston 12provided with annular grooves in which are fitted piston-rings 13. Thepiston has a rearward extension in the form. of a sleeve or skirt 14 inwhich is formed along a generator-line a longitudinal slot 15 in whichis engaged the heel 16 of the cocking link rod 6.

The piston 12 is also rigidly fixed to an axial rod 13, for example byscrewing the portion 17 of said piston into said rod, there being fittedover said axial rod a coil spring 11 which works in compression and oneend of which is applied against the end 20 of the sleeve 14 whilst theother end is applied against an abutment shoulder provided at the rearof the receiver 1.

When the moving system 19 is located in the forward position thereof,the heel 16 of the link-rod 6 is located at the rear end of the slot 15with the result that, when the operating arm 5 is caused to pivot aboutits pin 4 so as to move said arm away from the barrel 3, thedisplacement of the heel 16 initiates the rearward displacement of themoving system 19. Said moving system can be maintained in this cockedposition by means of a firing mechanism controlled by a trigger, saidmechanism being capable of producing action on the rod 18 which isrigidly fixed to the piston 12.

In order to maintain the arm 5 in the rest position underneath thebarrel 3 (as shown in FIGS. 1 and 2), provision has been made for afastening lug 21 or catch which is integral with said barrel and whichis capable of penetrating through a hole 50 into a socket 22 which isthrust back in the closed position (position of engagement with thecatch 21) by a spring 23 which is applied against the bottom of a cap 24which is screwed onto the extremity of the arm 5.

The socket 22 is provided with a stud 25 which is capable of slidingfreely within a slot 26 formed for this purpose in the arm 5. When thestud is thrust forward inside the cap 24 in opposition to the spring 23,the socket 22 can accordingly be released from the catch 21, thus makingit possible to release the arm 5, and then to carry out the cockingmovement.

The cylinder head 9 has a frusto-conical boss 27 which projects into theinterior or compression chamber of the pump and onto the frusto-conicalsurface of which open ducts 28 providing communication with an axialduct 29 which connects said compression chamber 30 of the pump to theloading chamber 3a which is located to the rear of the gun barrel 3.

Within the axial duct 29 is fitted a valve 31 which is preferablymaintained in the open position against a stop by a spring 32 whichbears against an annular shoulder 33 of the duct 29 and against the base34 of the valve 31. The spring 32 is thus protected by the valve 31against the temperature rise which occurs at the time of ignition of theexplosive charge contained in the loading chamber 3a.

The loading chamber 3a and its extension 9b which is formed within thecylinder head 9 are provide-d with longitudinal grooves 36 (as shown inFIGS. 3 and 4) which permit the air to .pass in both directions when thevalve is open, which takes place continuously except at the moment ofexplosion of the charge when said valve is violently applied against anannular seating 37 which is formed at the rear end of the extension 92)of the loading chamber.

During the suction stroke of the piston 12, the spring 32 prevents thevalve 31 from being applied against the seating 37.

The obturation which is ensured by the valve 31 at the time of explosionof the charge is completed by the obturation which is produced owing tothe fact that the front face of the piston 12 has a frusto-conicaldepression or recess 38 having a shape which is complementary to that ofthe boss 27,'with the result that, when the piston 12 has reached thelimit of its working stroke, it seals off the openings of the ducts 28by virtue of its recess 38.

FIG. 5 represents a preferred from of embodiment of the ammunition unitwhich is designed for use with the rifle for the practical applicationof this invention.

The ammunition unit referred-to comprises at the front end theprojectile 41 proper (which forms a temporary valve at the front portionof the loading chamber 311 when the pressure initially rises). Saidprojectile or body is provided at the rear end with a skirt 42 having adiameter which is smaller than that of said projectile in order that thehigh pressure which is generated when a shot is fired can be balanced:both inside and outside the skirt which is thus not liable to burst.

Inside the skirt 42 is placed a first explosive charge 43 of a standardtype commonly employed and a second charge 44 having a base ofstabilized and treated guncotton (or any other compound which is capableof igniting under the action of a diesel effect) which is designed toignite the first charge 43.

In an alternative form, the two charges 43 and 44 can be mixed so as toform a single charge which is capable of igniting spontaneously bydiesel effect.

The alternative form of ammunition unit shown in FIG. 7 differs from thefirst in that the skirt 42 has an aperture 45 which permits the escapeof gases with a view to balancing the pressure outside and inside theskirt.

The ammunition unit shown in FIG. 8, in which the skirt is againprovided with a communication aperture 45, differs from the precedingunits in that the skirt 42 is provided at its rear extremity with anannular mass 47 with a view to ensuring better guiding of theprojectile.

Irrespective of the type of ammunition unit employed, the positioning ofsaid unit within the loading chamber 3b is obtained by inserting saidunit inside said chamber under a light pressure applied by the cylinderhead 9 at the moment of closure of the breech, the front portion of theprojectile being accordingly engaged within the inlet of the bore of thegun barrel 3 so as to form a leak-tight seal therein at the moment ofpressurization of the compressed air, said seal thus forming at thatmoment a sufficient brake to prevent any displacement of the projectilewhen the diesel effect is produced.

When the user proceeds to fire the gun, the moving system 19 which haspreviously been placed in the cocked position is projected forward,thereby producing the rapid compression of the air which is presentwithin the work chamber 30 of the pump, this compression beingpropagated into the loading chamber 3a-9b for the firing of the charge.

Furthermore, when the piston 12 has reached the limit of its workingstroke, there is present between the boss 27 and the correspondingrecess 38 of the piston 12 a damping air cushion which reduces thehammering action between the moving and stationary elements of the pumpto a considerable extent. The filling of the chamber 30 with fresh airduring the cocking operation can be facilitated by means of a ductformed within the piston 12 and controlled by a valve.

It will be noted that this mode of ignition by compression of the chargemakes it possible to dispense with the striker-pin of conventionalfirearms and with the usual cartridge case of ammunition units in viewof the fact that the novel ammunition unit according to the inventiondoes not require the use of any primer with fulminate base.

It will be apparent that the example of embodiment of the rifle whichhas been described hereinabove and illustrated in the accompanyingdrawings is not given in any limiting sense and that any and all detailmodifications can be made in said embodiment without thereby departingfrom the spirit oi the invention, which also includes within its scopeall other devices for the propulsion of objects other than a rifle andentailing the application of general means which form the basis of theinvention as defined in the appended claims.

What I claim is:

1. In a device for firing objects of the class of projectiles, plugs,pins and nails which are intended to be propelled under the action of anexplosive charge of the type in which the ignition of said charge takesplace under the action of a pressure rise, said device comprising asupporting stock, a gun barrel mounted in said stock, a compressed-airpump which is disposed to the rear of said barrel so as to providetherewith a space forming a loading chamber and which has a cylinder anda piston movable within said cylinder, there being formed in that end ofsaid pump cylinder which is directed towards said barrel at least oneduct providing a communication between the loading chamber and theinterior of said cylinder, elastic control means for said piston whichare placed against the rear face of the piston and tend to drive saidpiston into' the cylinder so as to compress the air contained thereinand to deliver the air under pressure into the loading chamber, andcocking means for withdrawing the piston relatively to the cylinder-endand at the same time for compressing the elastic control means, the factthat the working face of the piston is provided with a substantiallyfrustoconical axial recess, whilst the cylinder-end is provided with afrusto-conical boss having a shape which is complementary to that ofsaid recess and with means for admitting air through said boss so as toenable the pump cylinder to communicate with the loading chamber.

2. Firing device as defined in claim 1, wherein the air-admission meanscomprise at least one duct of which one extremity has its opening on thefrusto-conical surface of the cylinder-end boss, a valve disposed withinsaid duct and capable of sealing off said duct when an overpressure isproduced within the loading chamber, and a spring which produces actionon the valve so as to maintain said valve in the normally open position.

References Cited by the Examiner UNITED STATES PATENTS 2,574,147 11/1951Hobbs 897 2,947,221 8/1960 Griffin et a1. 89-7 FOREIGN PATENTS 1,321,7462/1963 France.

5,317 1/1826 Great Britain. 571,163 8/1945 Great Britain.

BENJAMIN A. BORCHELT, Primary Examiner.

SAMUEL FEINBERG, Examiner.

S. W. ENGLE, Assistant Examiner.

1. IN A DEVICE FOR FIRING OBJECTS OF THE CLASS OF PROJECTILES, PLUGS, PINS AND NAILS WHICH ARE INTENDED TO BE PROPELLED UNDER THE ACTION OF AN EXPLOSIVE CHARGE OF THE TYPE IN WHICH THE IGNITION OF SAID CHARGE TAKES PLACE UNDER THE ACTION OF A PRESSURE RISE, SAID DEVICE COMPRISING A SUPPORTING STOCK, A GUN BARREL MOUNTED IN SAID STOCK, A COMPRESSED-AIR PUMP WHICH IS DISPOSED TO THE REAR OF SAID BARREL SO AS TO PROVIDE THEREWITH A SPACE FORMING A LOADING CHAMBER AND WHICH HAS A CYLINDER AND A PISTON MOVABLE WITHIN SAID CYLINDER, THERE BEING FORMED IN THAT END OF SAID PUMP CYLINDER WHICH IS DIRECTED TOWARDS SAID BARREL AT LEAST ONE DUCT PROVIDING A COMMUNICATION BETWEEN THE LOADING CHAMBER AND THE INTERIOR OF SAID CYLINDER, ELASTIC CONTROL MEANS FOR SAID PISTON WHICH ARE PLACED AGAINST THE REAR FACE OF THE PISTON AND TEND TO DRIVE SAID PISTON INTO THE CYLINDER SO AS TO COMPRESS THE AIR CONTAINED THEREIN AND TO DELIVER THE AIR UNDER PRESSURE INTO THE LOADING CHAMBER, AND COCKING MEANS FOR WITHDRAWING THE PISTON RELATIVELY TO THE CYLINDER-END AND AT THE SAME TIME FOR COMPRESSING THE ELASTIC CONTROL MEANS, THE FACT THAT THE WORKING FACE OF THE PISTON IS PROVIDED WITH A SUBSTANTIALLY FRUSTOCONICAL AXIAL RECESS, WHILST THE CYLINDER-END IS PROVIDED WITH A FRUSTO-CONICAL BOSS HAVING A SHAPE WHICH IS COMPLEMENTARY TO THAT OF SAID RECESS AND WITH MEANS FOR ADMITTING AIR THROUGH SAID BOSS SO AS TO ENABLE THE PUMP CYLINDER TO COMMUNICATE WITH THE LOADING CHAMBER. 